ABC trial (A011502): A randomized phase III double blinded placebo controlled trial of aspirin as adjuvant therapy for node positive breast cancer.

Abstract

TPS586 Background: In-vitro and in-vivo evidence suggest that aspirin, an inexpensive and widely available drug may have anti-tumor activity via effects on multiple pathways. Multiple epidemiologic studies have reported improved breast cancer survival among regular aspirin users compared to non-users. Furthermore, pooled data from randomized trials of aspirin for cardiovascular disease have also reported a decreased risk of metastatic cancer among aspirin users, especially metastatic adenocarcinoma (RR 0.52 (95% CI 0.35-0.75). In order for aspirin to be considered standard of care, the exact benefits and risks for breast cancer survivors need to be confirmed in a randomized trial. Methods: The primary objective is to compare the effect of aspirin versus placebo upon invasive disease-free survival (iDFS) in stage II-III node-positive HER2 negative breast cancer patients. Secondary objectives include effects on overall survival and cardiovascular disease and to collect toxicity and adherence. A biospecimen repository will be created for future correlative analyses including tumor collection at baseline and blood and urine samples at baseline and 2 years. Questionnaires assessing lifestyle factors associated with inflammation (pain, sleep, stress, and depression) will also be collected at baseline and 2 years. Study design: Subjects will be randomized (1:1) to aspirin 300 mg vs placebo daily for 5 years in a double-blinded fashion. Stratification factors include hormone receptor status (positive vs negative), body mass index ( < or ≥ 30 kg/m2), and stage (II vs III).Subjects will be followed every 6 six months while on study drug and then annually until 10 years from registration. 2936 patients will be enrolled with 80% power to detect HR 0.75. Eligibility: Eligible subjects include patients aged 18-70 diagnosed with a primary invasive stage II or III node positive HER2 negative breast cancer in the past year. Patients who currently use any oral or injectable anticoagulant or those with a prior history of GI bleeding, atrial fibrillation, myocardial infarction, or grade IV hypertension will be excluded. Patients who regular used aspirin over the past year will be excluded. Clinical trial information: NCT02927249.